Research On Local-fan Control System Based On CAN Bus

Last year was the year full of accidents in mine production. There were 3639 death accidents and 6027 men died. Among those accidents, methane explosion was the main cause. Focusing on safety production in mine, the model of local-fan control system based on CAN bus is given in this article. It is aiming at solving the difficult problem of production accidents caused by gas concentration in working face, flow entrance and air return gateway exceeding standard and a wrong humanly switching on. In this article, CAN bus is used as the main line of monitoring and control network in device level and single-chip microcomputer as the controller of intelligent node. With the CAN/RS232 converting card and monitoring and control software, PC can realize the control of the local-fan system. In this article, technical characteristic and technical criterion is discussed firstly so as to give the reason theoretically for choosing the CAN bus as the main line of monitoring and control network in device level. Subsequently, the software, hardware and reliability designs of the intelligent node are discussed in detail. The hardware designs include four blocks:â‘  global hardware design ; â‘¡ power supplier design;â‘¢ control circuit design â‘£ interface circuit design. As to software designs, some important initial programs, bus receiving and transmitting program and subprogram are given in this article. Reliability designs include hardware anti-jamming design, software anti-jamming design and intrinsic safety design. And then, the software, hardware designs of CAN/RS232 converting card is also given to realize the transparent converting between RS232 bus and CAN bus. At last, the process of communication between PC and single-chip microcomputer via RS232 bus is discussed. After being programmed the PC monitoring and control software through Microsoft company's Visual C++ 6.0 developing station and tested by test station, the PC can realize the control of the local fans. After being tested in the lab and used in the locale, it manifests that the system runs stably and lives up to all the functions and meets the requirement of safety production in mine.